Why do some cats have two different eye colours?
Complete heterochromia means the two irises contain different amounts of pigment.
Topic illustration selected for this guide. Some learning images may be AI-assisted.Why do some cats have two different eye colours — the quick answer
✓ Complete heterochromia means the two irises contain different amounts of pigment.
✓ Record a clear baseline photo in natural light without flash.
✓ A new colour change, cloudiness, redness or unequal pupils needs prompt examination.
Complete heterochromia means the two irises contain different amounts of pigment. It can be a normal inherited feature, particularly in some white or white-spotted cats. Here is the useful version of the answer: how it works, what to monitor and when a physical change deserves veterinary attention.
The short answer
Complete heterochromia means the two irises contain different amounts of pigment. Normal appearance varies between cats, so compare with your cat's own baseline and pay attention to changes that persist.
How it works
It can be a normal inherited feature, particularly in some white or white-spotted cats. Age, genetics, pigmentation, anatomy, health and environment can all affect what you see, which is why context matters.
What to check
Compare both sides where relevant and look for pain, swelling, discharge, bleeding, cloudiness, altered movement, appetite change or a difference from clear earlier photographs. One feature is more useful when considered with the cat's overall comfort and routine.
What to do at home
Record a clear baseline photo in natural light without flash. Avoid forcing a repeat for a photo or testing a viral claim. The most cat-friendly response gives choice, protects safety and rewards calm alternatives.
What this does not tell you
Appearance alone cannot diagnose a medical condition or prove that a cat is healthy. Online photographs and general rules cannot replace an examination when a physical change is new, painful or persistent.
When to contact a veterinarian
A new colour change, cloudiness, redness or unequal pupils needs prompt examination. Seek faster help for breathing difficulty, collapse, seizures, major trauma, suspected poisoning, severe pain or repeated unsuccessful attempts to urinate.
Your quick checklist
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Three simple things you can do
You do not have to change everything today. Pick one step that feels realistic, try it and see how your cat responds.
- 1Record a clear baseline photograph in indirect natural light without flash.
- 2Check both eyes for equal comfort, clarity, pupil response and absence of discharge.
- 3Arrange prompt examination for any newly changing colour, cloudiness, redness, squinting or unequal pupils.
Common mistakes
×Assuming a newly different eye colour is harmless inherited heterochromia.
×Using flash or filters that distort the colour being monitored.
×Focusing on the attractive appearance while overlooking pain or vision change.
Questions cat people ask
What causes two different eye colours in a cat?+
Complete heterochromia reflects different amounts of iris pigment and can be a normal inherited feature, particularly in some white or white-spotted cats.
Can a cat's eye colour change later in life?+
A lasting new change is not the same as being born with two colours. Inflammation, injury and other eye disease can alter appearance, so prompt veterinary examination is important.
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Checked, dated and transparent
- Prepared by
- EverYes Cats editorial team
- Last updated
- 8 August 2026
- Source checked
- 8 August 2026
- Primary reference
- Cornell Feline Health Center ↗
We begin with the named reference, rewrite the information in plain language and add practical cat-parent steps. Urgent health statements are checked against veterinary sources. This guide has not been individually reviewed by a veterinarian unless explicitly stated. It provides education, not diagnosis or treatment.
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